Main

• Hayley Elliott as Lambkin Bones, Roger's daughter. She is a fun-loving sassy tomboy who has a secret underneath her tough exterior – she doesn't like the sea.
• Paul Bown as Roger Bones. A single father who is the patriarch of the family. He has a slightly sarcastic personality, and cannot co-ordinate things to achieve what he wants.
• Liz Smith as Gran, Roger's eccentric mother-in-law. Considering herself "a pirate and a half", she is a dab hand with a blunderbuss, and isn't afraid to fight hard. As the family's cook, her speciality is "mince pies made of squirmy things".
• Benjamin Rennis as Lawrence Kitten, a preteen streetwise boy who lives next door to the Bones family. Although he is often bemused by the family's antics, he and Lambkin are good friends.
• Rebecca Stevens as Grog Blossom Kate, one of Gran's old pirate crew from many years ago, who joins the Bones family when Gran herself invites her for a get-together. She sometimes clashes with Roger, who does not get on very well with her.

Minor characters

• Pustule the Macaw, Gran's pet macaw.
• Toby Sedgwick as The Man in the Sack. He is member of the Bones family whose identity is unknown, as his whole body is obscured by a sack.
• Andrew Sachs as Mr. Jones, Kittens' other next door neighbour, who leads a secret double life as the pirate Basmati Bill.
• Baby Bones, The youngest member of the Bones family, who is never seen, but his presence is often noted by a green glow coming out of his black pram.

Series 1

Series 2

Series 3